Many dispensers with no moving parts, e.g. "passive" dispensers, are known, for example, U.S. Pat. Nos. 650,161 to Williams et al; 1,175,032 to Williams; 3,504,384 to Radley et al; 4,171,546, 4,186,856 and 4,208,747 to Dirksing; 4,216,027 to Wages; 4,251,012 to Owens et al; 4,281,421 to Nyquist et al; 4,305,162 to Cornelisse, Jr. et al, and 4,307,474 to Choy.